This invention relates to a print wheel mounting assembly for a serial printer comprising a print wheel including a number of spokes radially outwardly extending from a hub in the center of the print wheel and each having at least one type element mounted thereon.
Heretofore, a type wheel, a type ball or a type pallet has been in use as a type element carrier of a serial printer. Such type element carrier is generally mounted on a type element selecting rotary shaft by means of a nut, a screw or a support ring and requires a screw driver, a wrench or a special tool for mounting or detaching same. Proposals have been made to use a print wheel mounting assembly including a special tool for mounting and clamping a print wheel assembled into the serial printer so as to eliminate the need to use a special tool for mounting or detaching the print wheel. For example, Japanese Laid-Open Patent Application No. Sho-51-70017 discloses a print wheel mounting assembly including a spring, a pin and a locking member connected to a type element selecting rotary shaft. This print wheel mounting assembly has disadvantages in that its construction is complex, that the print wheel tends to become wobbly axially thereof, and that difficulties are encountered in accurately positioning the print wheel. Other print wheel mounting assemblies known in the art include a cylindrical portion having inserted therein a type element selecting rotary shaft and attached to the hub of the print wheel to be clamped by a spring from outside or having resiliently force fitted therein a type element selecting rotary shaft. These assemblies all have the disadvantages that the axial position of the type element selecting rotary shaft is unstable, and that there is a possibility that the repeated printing of characters will cause dislodging of the print wheel from the forward end of the shaft.